Method of forming trench isolation regions

ABSTRACT

In accordance with an aspect of the invention, a method of forming a trench isolation region includes forming a trench within a substrate. A silanol layer is formed to partially fill the trench and then converted, at least some of the silanol, to a compound including at least one of SiO n  and RSiO n , where R includes an organic group. An electrically insulative material is formed over the converted silanol to fill the trench. In another aspect of the invention, a method of forming a trench isolation region includes forming a trench within a substrate. A first layer of at least one of Si(OH), and (CH 3 ) y Si(OH) 4-y  is formed to partially fill the trench. At least some of the Si(OH), if present is converted to SiO 2  and at least some of (CH 3 ) y Si(OH) 4-y  if present is converted to (CH 3 ),SiO 2-x . Next, a layer of an electrically insulative material is formed to fill the trench.

TECHNICAL FIELD

[0001] This invention relates to methods of forming trench isolationregions in semiconductive substrates.

BACKGROUND OF THE INVENTION

[0002] In modern semiconductor device applications, numerous devices arepacked onto a single small area of a semiconductor substrate to createan integrated circuit. For the circuit to function, many of theseindividual devices may need to be electrically isolated from oneanother. Accordingly, electrical isolation is an important and integralpart of semiconductor device design for preventing the unwantedelectrical coupling between adjacent components and devices.

[0003] As the size of integrated circuits is reduced, the devices thatmake up the circuits must be positioned closer together in order tocomply with the limited space available on a typical semiconductorsubstrate. As the industry strives towards a greater density of activecomponents per unit area of semiconductor substrate, effective isolationbetween circuits becomes all the more important.

[0004] The conventional method of isolating circuit components in modernintegrated circuit technology takes the form of trench isolation regionsetched into a semiconductor substrate. Trench isolation regions arecommonly divided into three categories: shallow trenches (STI) (trenchesless than about 1 micron deep); moderate depth trenches (trenches offrom about 1 to about 3 microns deep); and deep trenches (trenchesgreater than about 3 microns deep). Once the trench isolation regionsare etched in the semiconductor substrate, a dielectric material isdeposited to fill the trenches. As the density of components on the lsemiconductor substrate increased, the widths of the trenches decreaseduntil the process of flowing dielectric material into the trenchesdeveloped problems.

[0005] Trench isolation regions, particularly STI regions, can developundesirable voids in the dielectric material during the process to fillthe trenches. As the dielectric material flows to an edge between asubstrate surface and a sidewall of the trench, constrictions develop atthe top of trenches due to the narrow opening in the trench. As thedielectric material flows into the trench, the constrictions can developinto voids moving into the trench with the dielectric material. Voidslower the dielectric characteristics of the dielectric material used andintroduce structural instabilities in subsequent processes. Accordingly,voids in the dielectric material filling an isolation trench region arehighly undesirable.

SUMMARY OF THE INVENTION

[0006] In accordance with an aspect of the invention, a method offorming a trench isolation region includes forming a trench within asubstrate. A silanol layer is formed to partially fill the trench and Ithen at least some of the silanol is converted to a compound comprisingat least one of SiO_(n) and RSiO_(n), where R comprises an organicgroup. An electrically insulative material is formed over the convertedsilanol to fill the trench.

[0007] In another aspect of the invention, a method of forming a trenchisolation region includes forming a trench within a substrate. A firstlayer of at least one of Si(OH)_(x) and (CH₃)_(y)Si(OH)_(4-y) is formedto partially fill the trench. At least some of the Si(OH)_(x) if presentis converted to SiO₂ and at least some of (CH₃)ySi(OH)_(4-y) if presentis converted to (CH₃)_(x)SiO_(2-x). Next, a layer of an electricallyinsulative material is formed to fill the trench.

[0008] In yet another aspect of the invention, a method of forming atrench isolation region includes forming a trench within a substrate.The trench has sidewalls comprising silicon and a base comprisingsilicon. A first electrically insulative layer is formed over thesidewalls and base. The first electrically insulative layer isanisotropically etched to expose silicon of the base while leavingsilicon of the sidewalls covered. A second electrically insulative layeris substantially selectively chemical vapor deposited over the exposedtrench base. A third electrically insulative layer is formed over thefirst and second insulative layers to within the trench.

[0009] In still another aspect of the invention, a method of forming atrench isolation region includes forming a trench having sidewallswithin a substrate. The sidewalls are thermally oxidized in an oxidizingenvironment which includes oxygen and hydrogen with a greater molarconcentration of hydrogen than oxygen. A layer of silanol is formed towithin the trench and at least some of the silanol is converted to acompound of at least one of SiO_(n) and RSiO_(n), where R includes anorganic group.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Preferred embodiments of the invention are described below withreference to the following accompanying drawings.

[0011]FIG. 1 is a fragmentary sectional view of a semiconductorsubstrate at one processing step in accordance with a first embodimentof the invention.

[0012]FIG. 2 is a view of the FIG. 1 substrate fragment at a processingstep subsequent to that shown in FIG. 1.

[0013]FIG. 3 is a view of the FIG. 1 substrate fragment at a processingstep subsequent to that shown in of FIG. 2.

[0014]FIG. 4 is a view of the FIG. 1 substrate fragment at a processingstep subsequent to that shown in of FIG. 3.

[0015]FIG. 5 is a fragmentary sectional view of a semiconductorsubstrate at one processing step in accordance with a second embodimentof the invention.

[0016]FIG. 6 is a view of the FIG. 5 substrate fragment at a processingstep subsequent to that of FIG. 5.

[0017]FIG. 7 is a view of the FIG. 5 substrate fragment at a processingstep subsequent to that of FIG. 6.

[0018]FIG. 8 is a fragmentary sectional view of a semiconductorsubstrate at one processing step in accordance with a third embodimentof the invention.

[0019]FIG. 9 is a view of the FIG. 8 substrate fragment at a processingstep subsequent to that of FIG. 8.

[0020]FIG. 10 is a view of the FIG. 8 substrate fragment at a processingstep subsequent to that of FIG. 9.

[0021]FIG. 11 is a view of the FIG. 8 substrate fragment at a processingstep subsequent to that of FIG. 10.

[0022]FIG. 12 is a view of the FIG. 8 substrate fragment at a processingstep subsequent to that of FIG. 11.

[0023]FIG. 13 is a fragmentary sectional view of a semiconductorsubstrate at one processing step in accordance with a fourth embodimentof the invention.

[0024]FIG. 14 is a view of the FIG. 13 substrate fragment at aprocessing step subsequent to that of FIG. 13.

[0025]FIG. 15 is a view of the FIG. 13 substrate fragment at aprocessing step subsequent to that of FIG. 14.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] This disclosure of the invention is submitted in furtherance ofthe constitutional purposes of the U.S. Patent Laws “to promote theprogress of science and useful arts” (Article 1, Section 8).

[0027] With reference to FIGS. 1-4, a method of forming a trenchisolation region is illustrated. Referring to FIG. 1, a semiconductorsubstrate fragment in process is indicated generally with referencenumeral 10. Preferably, the semiconductor substrate fragment 10comprises the following layers shown in elevationally ascending order: asemiconductor substrate 12, preferably a bulk monocrystalline siliconsubstrate; an oxide layer 20; and a silicon nitrite layer 22. A seriesof trenches 14 are formed, preferably by an etching process, throughlayers 20 and 22 and within semiconductor substrate 12. Trench isolationregions 14 have sidewalls 16 and base walls 18.

[0028] Referring to FIG. 2, a first layer 26 is formed, and initiallycomprises a silanol which partially fills trenches 14. An exemplarymethod of forming the first layer 26 is as follows. SiH₄ and H₂O, areseparately introduced into a chemical vapor deposition (CVD) chamber,such as a parallel plate reaction chamber (not shown). The reaction ratebetween SiH₄ and H₂O₂ can be moderated by the introduction of nitrogeninto the reaction chamber. Semiconductive substrate 12 within thechamber is preferably maintained at a suitably low temperature, such as0° C., at an exemplary pressure of 1 Torr to achieve formation of asilanol-type material of the formula Si(OH)_(x), which is predominatelySi(OH)₄. The Si(OH)₄ condenses onto the semiconductor substrate 12surface to form layer 26.

[0029] Alternatively, first layer 26 is formed to comprise(CH₃)_(y)Si(OH)_(4-y) at least initially to partially fill the trench.The formation of (CH₃)_(y)Si(OH)_(4-y) can be accomplished similarly tothat described above for forming silanol, with the exception that(CH₃)_(z)SiH_(4-z), wherein z is at least 1 and no greater than 4, iscombined with the hydrogen peroxide (H₂O₂). For example, CH₃SiH₃ can becombined with H₂ 0 ₂ to produce CH₃Si(OH)₃.

[0030] Although either reaction occurs in the gas phase, the initiallydeposited first layer 26 (Si(OH)_(x) or (CH₃)_(y)Si(OH)_(4-y)) ispreferably in the form of a viscous liquid which preferably flows veryconformably, ideally depositing over trench base 18 faster and thickerthan over sidewalls 16. A preferred thickness for first layer 26 is atleast 25% of the trench depth, and more preferably at least 35%, whilepreferably adding only 200 angstroms or less to sidewalls 16.

[0031] After forming first layer 26 over semiconductor substrate 12, atleast some of it is converted to a compound comprising at least one ofSiO_(n) and RSiO_(n), where R comprises an organic group. An exemplaryprocess for doing so is to treat first layer 26 with energy to drivewater therefrom and convert to a silicon oxide comprising structure. Aspecific exemplary method of converting first layer 26 comprisesexposing the first layer 26 to ultraviolet light, with other examples ofenergy being electron beam energy or plasma, and RF energy. Preferably,a two-step process is employed. First, polymerization of the liquid filmis promoted by increasing the temperature to above 100° C., whilemaintaining the pressure of about 1 Torr, to result in solidificationand formation of a polymer layer. Thereafter, the temperature is raisedto above 300° C., preferably above 400° C., while maintaining a pressureof about 1 Torr, preferably at least 10 atmospheres.

[0032] Referring to FIG. 3, a second layer 30 is formed comprising anelectrically insulative material, preferably silicon dioxide, overconverted silanol layer 26 to within the trenches 14. Preferably asshown, second layer 30 is formed to fill remaining volume of trenches14. An exemplary process for forming second layer 30 comprises chemicalvapor deposition, preferably plasma-enhanced chemical vapor deposition.For example, conventional high density plasma deposited SiO₂ can beformed. In the context of this document, “high density” refers to aplasma having at least 10¹⁰ ions/cm³ plasma density. An optionalgettering process may be performed at this stage of the process.

[0033] Referring to FIG. 4, planarization can be conducted (i.e.,chemical-mechanical polishing) to remove layers 30, 22 and 20 from overthe substrate outside of trenches 14.

[0034] With reference to FIGS. 5-7, another embodiment in accordancewith the invention is described. Like numerals from the first describedembodiment are employed where appropriate, with differences beingindicated with a suffix (a) or with different numerals.

[0035] Referring to FIG. 5, a semiconductor substrate fragment inprocess is indicated generally with reference numeral 10 a. Anelectrically insulating first layer 40 is chemical vapor deposited towithin trenches 14 to partially fill the trenches. Preferably, firstlayer 40 comprises silicon dioxide (SiO₂) and fills at least 25% of thetrench 14 depth. First layer 40 is preferably deposited byplasma-enchanced chemical vapor deposition, preferably by high densityplasma or subatmospheric chemical vapor deposition.

[0036] Referring to FIG. 6, a second layer 44 comprising a silanol isformed over first layer 40 to within trenches 14. Preferably, the methodto form second layer 44 is by the same method previously discussed anddisclosed for forming first layer 26 of the FIGS. 1-4 embodiment.Consequently, as with the previous method, second layer 44 preferablyfills trenches 14, preferably is maintained at a temperature of at leastabout 300° C. and at a pressure of at least about 10 atmosphereseffective to drive water from second layer 44, and preferably isconverted to a silicon oxide comprising structure by exposure to energy,for example ultraviolet light.

[0037] Referring to FIG. 7, planarization can be conducted (i.e.,chemical-mechanical polishing) to remove layers 44, 40, 22 and 20 fromover the substrate outside of trenches 14.

[0038] With reference to FIGS. 8-12, yet another embodiment inaccordance with the invention is described. Like numerals from thepreviously described embodiments are employed where appropriate, withdifferences being indicated with a suffix (b) or with differentnumerals.

[0039] Referring to FIG. 8, a semiconductor substrate fragment inprocess is indicated generally with reference numeral 10 b. Anelectrically insulative layer 21 is formed over silicon trench sidewalls16 and trench base 18. An example thickness for layer 21 is 150angstroms. A preferred material for layer 21 is silicon dioxide. Anexemplary method of forming layer 21 comprises chemical vapordeposition, and alternatively thermal oxidation. An example thermaloxidation comprises flowing an oxidizing gas (i.e., O₂, O₃, N_(l)O,NO_(x) or any mixture combination thereof) over substrate 12 withintrenches 14 while substrate 12 is maintained at from 850° C. to 1150° C.for from 5 to 30 minutes. An example chemical vapor deposition processcomprises injecting tetraethylorthosilicate (TEOS) into a reactorchamber at 500 mg/min while flowing O₃, preferably as a mixture of 12%O₃ and 88% O₂, at 4000 sccm and helium at from 0-200 sccm andmaintaining the substrate 12 at 550° C. and reactor pressure at 200Torr.

[0040] Referring to FIG. 9, insulative layer 21 is anisotropicallyetched to expose silicon of the base walls 18 while leaving silicon ofthe sidewalls 16 covered. An exemplary anisotropic etch comprises aconventional oxide spacer etch.

[0041] Referring to FIG. 10, a second electrically insulative layer 50is substantially selectively deposited over the exposed base walls 18 topartially fill the trenches 14. Preferably, layer 50 comprises an oxidedeposited by chemical vapor deposition, and more preferably silicondioxide. An exemplary chemical vapor deposition to form layer 50comprises liquid injecting TEOS into a reactor chamber at 350 mg/minwhile flowing O₃, preferably as a mixture of 12% O₃ and 88% O₂, at 5000sccm and helium at from 0-200 sccm and maintaining the substrate 12 at400° C. and reactor pressure at 600 Torr.

[0042] Referring to FIG. 11, a layer 30 is formed comprising anelectrically insulative material, preferably silicon dioxide, overlayers 21, 22 and 50 to within trenches 14. Preferably as shown, layer30 is formed to fill remaining volume of trenches 14. An exemplaryprocess for forming second layer 30 comprises chemical vapor deposition,preferably high density plasma-enhanced chemical vapor deposition asdescribed above. An alternative method of forming layer 30 comprisesflowing a silanol layer to fill within trenches 14. The method to formlayer 30 is preferably by the same method previously discussed anddisclosed for forming first layer 26 of the first embodiment shown inFIGS. 1-4 and second layer 44 of the second embodiment shown in FIGS.5-7.

[0043] Referring to FIG. 12, planarization can be conducted (i.e.,chemical-mechanical polishing) to remove layers 30, 22, 21 and 20 fromover substrate 12 outside of trenches 14.

[0044] With reference to FIGS. 13-15, still another embodiment inaccordance with the invention is described. Like numerals from the firstdescribed embodiment are employed where appropriate, with differencesbeing indicated with a suffix (c) or with different numerals. Referringto FIG. 13, an electrically insulative layer 21 is formed over silicontrench sidewalls 16 and trench base 18 by a thermal oxidization process.An exemplary method of forming layer 21 comprises thermally oxidizingthe sidewalls of the trench in an oxidizing environment comprisingoxygen and hydrogen and having a greater molar concentration of hydrogenthan oxygen. An example thermal oxidation comprises flowing an oxidizinggas at 200 sccm (i.e., O₂, O₃, N₂O, NO_(x) or any mixture combinationthereof) and hydrogen source at 1 slm (i.e., H₂, NH₃ or any mixturecombination thereof) over substrate 12 within trenches 14. Preferably,substrate 12 is maintained at from 800° C. to 1100° C. and reactorpressure is at from 10 Torr to 760 Torr for from 1 to 20 minutes.

[0045] Referring to FIG. 14, a silanol layer 44 is formed over layers 21and 22 to within trenches 14. At least some of the silanol is convertedto a compound comprising at least one of SiO_(n) and RSiO_(n), where Rcomprises an organic group. The method to form layer 44 is preferably bythe same method previously discussed and disclosed for forming firstlayer 26 of the first embodiment shown in FIGS. 1-4 and second layer 44of the second embodiment shown in FIGS. 5-7.

[0046] Referring to FIG. 15, planarization can be conducted (i.e.,chemical-mechanical polishing) to remove layers 44, 22, 21 and 20 fromover substrate 12 outside of trenches 14.

[0047] Alternatively, the silanol 44 could be formed within trenches 14and converted before a sidewall oxidation. Preferably in such instance,8 the thermal oxidation conditions comprise flowing an oxidizing gas at200 sccm (i.e., O₂, O₃, N₂O, NO_(x) or any mixture combination thereof)over substrate 12 within trenches 14 while substrate 12 is maintained atfrom 850° C. to 1150° C. and reactor pressure at from 10 Torr to 760Torr for from 5 to 30 minutes.

[0048] Further in accordance with the invention, sidewalls 16 might beoxidized prior to forming first layer 26 in the first embodiment, orprior to forming first layer 40 in the second embodiment. Alternately,sidewalls 16 might be oxidized after forming first layer 26 and beforeforming second layer 30 in the first embodiment, or after forming firstlayer 40 and before forming second layer 44 in the second embodiment orafter forming layer 50 and before forming layer 30 in the thirdembodiment. Further alternately, sidewalls 16 might be oxidized afterforming second layer 30 in the first embodiment, or after forming layer44 in the second embodiment. Further alternately with respect to thethird embodiment, and where layer 21 is not formed by thermal oxidation,the sidewalls might be oxidized after forming layer 50 and beforeforming layer 30, or after forming layer 50. Conventional thermaloxidations are preferably conducted in such instances.

[0049] In the preferred first embodiment, first layer 26 flowsconformably into the trenches during deposition without forming anyconstrictions at the top of the trenches where voids begin. The firstlayer 26 effectively lowers the aspect ratio (defined as trench depth towidth) of the trenches preferably by filling at least about a third ofthe depth while only adding at most 200 angstroms of layer on thesidewalls. As a result, any subsequent layer deposited to fill the layerwill have a trench with a lower aspect ratio more conducive to fillingwithout voids.

[0050] In the less preferred second and third embodiments, the firstlayer is formed by less preferred methods which may not lower the aspectratio as significantly as in the first embodiment.

[0051] In compliance with the statute, the invention has been describedin language more or less specific as to structural and methodicalfeatures. It is to be understood, however, that the invention is notlimited to the specific features shown and described, since the meansherein disclosed comprise preferred forms of putting the invention intoeffect. The invention is, therefore, claimed in any of its forms ormodifications within the proper scope of the appended claimsappropriately interpreted in accordance with the doctrine ofequivalents.

1. A method of forming a trench isolation region comprising: forming atrench within a substrate; forming a first layer comprising a silanol topartially fill the trench; converting at least some of the silanol to acompound comprising at least one of SiO_(n) and RSiO_(n), where Rcomprises an organic group; and forming a second layer comprising anelectrically insulative material over the converted silanol to withinthe trench.
 2. The method of claim 1 wherein the trench has sidewalls,and further comprising thermally oxidizing at least some of the trenchsidewalls intermediate the converting and the forming of the secondlayer.
 3. The method of claim 1 wherein the trench has a trench depth,the first layer filling at least 25% of the trench depth.
 4. The methodof claim 1 wherein the trench has a trench depth, the first layerfilling 35% or less of the trench depth.
 5. The method of claim 1wherein the second layer fills the trench.
 6. The method of claim 1wherein the silanol comprises methyl silanol and R is a methyl group. 7.The method of claim 1 wherein the second layer is formed by chemicalvapor deposition.
 8. The method of claim 1 wherein the second layer isformed by plasma-enhanced chemical vapor deposition.
 9. The method ofclaim 1 wherein the second layer comprises SiO₂.
 10. The method of claim9 wherein the SiO₂ is formed by a high density plasma.
 11. The method ofclaim 1 wherein the trench comprises sidewalls, thermally oxidizing thesidewalls prior to forming the first layer.
 12. The method of claim 1wherein the trench comprises sidewalls, thermally oxidizing thesidewalls after forming the first layer and before forming the secondlayer.
 13. The method of claim 1 wherein the trench comprises sidewallsand the first layer adds 200 angstroms or less of layer to thesidewalls.
 14. The method of claim 1 wherein prior to forming the secondlayer, maintaining the first layer at a temperature of at least about300° C. and at a pressure of at least about 10 atmospheres effective todrive water from first layer.
 15. The method of claim 1 whereinconverting the first layer comprises exposing the first layer toultraviolet light.
 16. A method of forming a trench isolation regioncomprising: forming a trench within a substrate; chemical vapordepositing an electrically insulating first layer to within the trenchto partially fill the trench; forming a second layer comprising asilanol over the first layer to within the trench; and converting atleast some of the silanol to a compound comprising at least one ofSiO_(n) and RSiO_(n), where “R” comprises an organic group.
 17. Themethod of claim 16 wherein the trench is formed in silicon, and whereinthe chemical vapor depositing comprises substantially selectivelydepositing an oxide over exposed silicon within the trench.
 18. Themethod of claim 17 wherein the substantially selectively depositing theoxide comprises flowing O₃ and TEOS to within the trench.
 19. The methodof claim 16 wherein the trench comprises silicon-comprising sidewallsand a silicon-comprising base, and further comprising forming anelectrically insulative layer over the sidewalls and the base;anisotropically etching the insulative layer to expose silicon of thebase while leaving silicon of the sidewalls covered; and the chemicalvapor depositing comprising substantially selectively depositing anoxide over the exposed trench base.
 20. The method of claim 19 whereinthe forming of the electrically insulative layer comprises chemicalvapor deposition.
 21. The method of claim 19 wherein the electricallyinsulative material comprises silicon dioxide, and the forming of theelectrically insulative layer comprises thermal oxidation.
 22. Themethod of claim 16 wherein the trench has sidewalls, and furthercomprising thermally oxidizing at least some of the trench sidewallsintermediate the chemical vapor depositing and the forming of the secondlayer.
 23. The method of claim 16 wherein the trench has a trench depth,the first layer filling at least 25% of the trench depth.
 24. The methodof claim 16 wherein the second layer fills the trench.
 25. The method ofclaim 16 wherein the silanol comprises methyl silanol and R is a methylgroup.
 26. The method of claim 16 wherein the first layer is depositedby plasma-enhanced chemical vapor deposition.
 27. The method of claim 16wherein the first layer comprises SiO₂.
 28. The method of claim 27wherein the SiO₂ is deposited by a high density plasma.
 29. The methodof claim 16 further comprising thermally oxidizing sidewalls of thetrench prior to depositing the first layer.
 30. The method of claim 16further comprising thermally oxidizing sidewalls of the trench afterdepositing the first layer and before forming the second layer.
 31. Themethod of claim 16 further including maintaining the second layer at atemperature of at least about 300° C. and at a pressure of at leastabout 10 atmospheres effective to drive water from the second layer. 32.The method of claim 16 wherein converting the second layer comprisesexposing the second layer to ultraviolet light.
 33. A method of forminga trench isolation region comprising: forming a trench within asubstrate, the trench comprising silicon-comprising sidewalls and asilicon-comprising base; forming a first electrically insulative layerover the sidewalls and base; anisotropically etching the firstelectrically insulative layer to expose silicon of the base whileleaving silicon of the sidewalls covered; substantially selectivelychemical vapor depositing a second electrically insulative layer overthe exposed trench base; and forming a third electrically insulativelayer over the first and second insulative layers to within the trench.34. The method of claim 33 wherein the third electrically insulativelayer comprises a silanol, and further comprising converting at leastsome of the silanol to a compound comprising at least one of SiO_(n) andRSiO_(n), where R comprises an organic group.
 35. The method of claim 34wherein the silanol comprises methyl silanol and R is a methyl group.36. The method of claim 33 wherein the substantially selectivelydepositing comprises flowing O₃ and TEOS to within the trench to form anoxide.
 37. The method of claim 33 wherein the third electricallyinsulative layer comprises SiO₂.
 38. The method of claim 33 wherein thethird electrically insulative layer is formed by plasma-enhancedchemical vapor deposition.
 39. A method of forming a trench isolationregion comprising: forming a trench within a substrate, and the trenchcomprising sidewalls and a base; thermally oxidizing the sidewalls andbase of the trench in an oxidizing environment, the oxidizingenvironment comprising oxygen and hydrogen and having a greater molarconcentration of hydrogen than oxygen; forming a layer comprising asilanol to within the trench; and converting at least some of thesilanol to a compound comprising at least one of SiO_(n) and RSiO_(n),where R comprises an organic group.
 40. The method of claim 39 whereinthe silanol comprises methyl silanol and R is a methyl group.
 41. Themethod of claim 39 wherein the oxidizing environment further comprisesmaintaining the substrate at from 800° C. to 1100° C.
 42. The method ofclaim 39 wherein the oxidizing environment further comprises maintainingthe substrate within a reactor having a pressure at from 10 Torr to 760Torr.
 43. The method of claim 39 wherein the oxidizing environmentfurther comprises maintaining the substrate within a reactor at from800° C. to 1100° C. and a pressure at from 10 Torr to 760 Torr.
 44. Amethod of forming a trench isolation region comprising: forming a trenchwithin a substrate, and the trench comprising sidewalls and a base;forming a layer comprising a silanol to within the trench; converting atleast some of the silanol to a compound comprising at least one ofSiO_(n) and RSiO_(n), where R comprises an organic group; and after theconverting, thermally oxidizing the sidewalls and base of the trench inan oxidizing environment.
 45. The method of claim 44 wherein the silanolcomprises at least one of Si(OH)_(x) and (CH₃)_(y)Si(OH)_(4-y), and theconverting comprises converting at least some of the Si(OH), if presentto SiO₂ and at least some of (CH₃)_(y)Si(OH)_(4-y) if present to(CH₃)_(x)SiO_(2-x).
 46. The method of claim 44 wherein the oxidizingenvironment further comprises maintaining the substrate in a reactor atfrom 850° C. to 1150° C. and a pressure at from 10 Torr to 760 Torr. 47.A method of forming a trench isolation region comprising the followingsteps: forming a trench within a substrate; forming a first layercomprising at least one of Si(OH), and (CH₃)_(y)Si(OH)_(4-y) topartially fill the trench; converting at least some of the Si(OH), ifpresent to SiO₂ and at least some of (CH₃)_(y)Si(OH)_(4-y) if present to(CH₃)_(x)SiO_(2-x); and after the converting, forming a second layercomprising an electrically insulative material to within the trench. 48.The method of claim 47 wherein the trench has sidewalls, and furthercomprising thermally oxidizing at least some of the trench sidewallsintermediate the converting and the forming of the second layer.
 49. Themethod of claim 47 wherein the trench has a trench depth, the firstlayer filling at least 25% of the trench depth.
 50. The method of claim47 wherein the second layer comprises SiO₂.
 51. The method of claim 50wherein the SiO₂ is formed by a high density plasma.
 52. The method ofclaim 47 wherein the trench comprises sidewalls, and further comprisingthermally oxidizing the sidewalls prior to forming the first layer. 53.The method of claim 47 wherein the trench comprises sidewalls, andfurther comprising thermally oxidizing the sidewalls after forming thefirst layer and before forming the second layer.
 54. The method of claim47 wherein the trench comprises sidewalls and the first layer adds 200angstroms or less of layer to the sidewalls.
 55. A method of forming atrench isolation region comprising the following steps: forming a trenchwithin a substrate; forming a high density plasma proximate thesubstrate to deposit a first layer of material to partially fill thetrench; forming a second layer comprising at least one of Si(OH), and(CH₃)_(y)Si(OH)_(4-y) over the first layer to within the trench; andconverting at least some of the Si(OH), if present to SiO, and at leastsome of (CH₃)_(y)Si(OH)_(4-y) if present to (CH₃)_(x)SiO_(2-x).
 56. Themethod of claim 55 wherein the trench has sidewalls, and furthercomprising thermally oxidizing at least some of the trench sidewallsintermediate the forming of the high density plasma and the forming ofthe second layer.
 57. The method of claim 55 wherein the trench has atrench depth, the first layer filling at least 25% of the trench depth.58. The method of claim 55 wherein the second layer fills the trench.59. The method of claim 55 wherein the first layer comprises SiO₂. 60.The method of claim 55 wherein the trench comprises sidewalls, andfurther comprising thermally oxidizing the sidewalls prior to formingthe first layer.
 61. The method of claim 55 wherein the trench comprisessidewalls, and further comprising thermally oxidizing the sidewallsafter forming the first layer and before forming the second layer. 62.The method of claim 55 further including maintaining the second layer ata temperature of at least about 300° C. and at a pressure of at leastabout 10 atmospheres effective to drive water from second layer.
 63. Themethod of claim 55 wherein converting the second layer comprisesexposing the second layer to ultraviolet light.